
var arr = [29, 45, 51, 68, 72, 97];
for (var i = 0; i < arr.length - 1; i++) {
    for (var j = 0; j < arr.length - 1 - i; j++) {
        if (arr[j] > arr[j + 1]) {
            var temp = arr[j];
            arr[j] = arr[j + 1];
            arr[j + 1] = temp;
        }
    }

}
console.log(arr);//[2, 4, 5, 12, 31, 32, 45, 52, 78, 89]